This invention relates to door frame components, and more particularly to such frame components which are formed from extruded material, such as extruded aluminum.
Extruded frame components for use in doors, such as storm doors and screen doors, are frequently formed from extruded aluminum stock, and joined together at the corners. Commonly, mitered corners are desirable by reason of an attractive appearance and their relative ease of manufacture. However, straight or simple mitered corners, in the absence of special attaching devices, do not always provide sufficient rigidity or strength so as to prevent the door from warping or sagging. The latter is a particular problem in storm doors which, during the winter months, carry glass inserts which substantially add to the weight carried by the door frame.
In the interest of reducing cost, many door frame components are made of narrower or lighter weight materials. These materials are more difficult to join together in a non-sagging form, at the corners, due at least in part to the reduction in the extent of confronting or abutting materials available to form a rigid construction. The latter is particularly true in making T-corners and simple or mitered corners.